package com.sky.aspect;
import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面类
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {


    //切入点
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")   //mapper包下面的所有方法并且方法中带有AutoFill注解的才可以被增强到
    public void autoFillPointcut(){}


    @Before("autoFillPointcut()")
    public void autoFill(JoinPoint joinPoint){

        //获取到当前被拦截的方法上的数据库操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();  //方法签名对象
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);  //获得方法上的注解对象
        OperationType value = autoFill.value();  //获得数据库操作类型

        //获取当前被拦截的方法的参数--实体类
        Object[] args = joinPoint.getArgs();
        if (args==null || args.length==0){
            return;
        }

        Object entity=args[0];  //获得实体对象

        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();

        if (OperationType.INSERT==value){
            //为4个公共属性赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射为对象属性赋值
                setCreateTime.invoke(entity,now);
                setCreateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }else if (OperationType.UPDATE==value){
            //为2个公共属性赋值
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射为对象属性赋值
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
